Rio de Janeiro, Brazil
Rio de Janeiro, Brazil

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Menezes R.R.,Federal University of Paraiba | Melo L.R.L.,IFCE | Fonseca F.A.S.,Aluno de Graduacao | Souto P.M.,Federal University of São Carlos | And 2 more authors.
Revista Escola de Minas | Year: 2010

The mining and processing industries of laminated calcite tile are an important economic sector in the State of Ceará. However, they generate a large amount of wastes, which are a source of contamination and environmental pollution. This study aimed to characterize the laminated calcite tile sawing waste and evaluate its suitability as an alternative ceramic raw material for the production of bricks and roof tiles. The waste was characterized by chemical composition determination, X-ray diffraction, differential thermal analyses, particle size distribution determination, and morphological analysis by electronic scanning microscopy. Several formulations were prepared and sample bodies were prepared by uniaxial pressing. The sample bodies were fired at different temperatures. Sintered samples were characterized in terms of water absorption and mechanical strength. The results showed that the waste is composed of calcite and dolomite, that presents a high level of fines. As such, it is possible to incorporate up to 10% for the production of ceramic bricks and roof tiles.

Lopes F.C.F.,Embrapa Gado de Leite | Dornelas R.A.C.,Embrapa Gado de Leite | Carneiro J.C.,Embrapa Gado de Leite | Verneque R.S.,Embrapa Gado de Leite | And 3 more authors.
Arquivo Brasileiro de Medicina Veterinaria e Zootecnia | Year: 2010

The values of in vitro dry matter digestibility (IVDMD) of four corn silages and six concentrates (three proteic and three energetics) were determined by the two-stage technique that utilizes individual digestion tubes and by an automatic equipment of fermentation (filter bag technique). It was also evaluated the associative effect on digestion of these three food classes when incubated in the same fermentation jar of the "in vitro incubator" and when in different vessels containing the same class of foods. The experimental design was completely randomized in a 3 x 3 factorial arrangement (in vitro procedures x food classes). The IVDMD values determined in tubes were closer to those found in the literature and lower (P<0.02) than those obtained by the automatic procedure. No differences were found (P>0.05) in IVDMD of concentrates and silages when incubated together in the same fermentation jar or separated by food classes in separated jars.

Gewehr C.E.,CAV | de Oliveira V.,Federal University of Santa Catarina | Miquelluti D.J.,CAV | Rosnicek M.,Aluno de graduacao | Farias D.K.,Aluno de graduacao
Archives of Veterinary Science | Year: 2010

Aiming to evaluate the effect of diets containing different particle size of corn on the performance of semi-heavy laying hens during the initial phase production, we used 392 Hy Line Brown birds reared on a bed of wood shavings, which received a balanced diet according with the requirement phase, distributed in four treatments in a completely randomized design with seven replicates. The treatments consisted of diets containing corn with Geometric Mean Diameter (GMD) of 0.66 mm, 1.26 mm, 3.21 mm and whole maize. No significant difference (P>0.05) in egg production (% eggs/hen/day), feed intake (g/bird/day), gravity (g/cm3), weight (g) egg mass (g). However, the diet with whole maize was better (P<0.05) feed conversion (g/g). Corn with different particle sizes can be used in food rations for semi-heavy birds during the laying phase without reducing performance and affect the quality of eggs.

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